Active Signal Processing: A Counter-intuitive Approach to Enhancing Signal-to-Noise Ratio via Noise Injection

Abstract

ABSTRACTSince its origin in the early 1980s, the noise-injection based stochastic resonance technique has spearheaded a novel counter-intuitive approach toward improving sensor performance. Within this approach, named Active Signal Processing, instead of removing system noise by filtering (Passive Signal Processing), it is possible to improve signal-to-noise ratio (SNR) by injecting noise into the measurement. ViaLogy LLC. has pioneered the development and demonstration of Quantum Resonance Interferometry (QRI), a quantum stochastic resonance (QSR)-based technique for improving SNR. The core of QRI processing involves the QSR-based generation of a Quantum Expressor Function (QEF), which characterizes the system of interest by encoding within it the noise environment, minimum level of detection, and the precision of measurement. Using digital post-processing of sensor information, QRI can determine the presence of a signal by the destruction of the resonance condition responsible for generating the system QEF. For applications aimed at detecting the presence of a weak signal, the strength of the signal is proportional to the number of iterations of the algorithm required for destruction of the resonance; the fewer the iterations, the stronger the signal. The application of QRI for detecting the presence of weakly expressing genes in fluorescent DNA microarrays will be described.